4.35% is the change from 643 to 671
Calculation steps:
[( 671 - 643 ) ÷ 643] x 100 = 4.35%
Formula
Percentage change = [(671 - 643) / 643] x 100
Subtract the new number by the original number
671 - 643 = 28
28 ÷ 643 = 0.04354587869362364
0.04354587869362364 x 100 = 4.35%